Key to the genus Eulophia group F
Sepals and petals of similar length and width, if sepals longer then flowers not opening widely.

1 Leaves well developed at flowering time  2
1a Leaves absent or just starting to develop at flowering time, or leaves vestigial  7
2 Sepals less than 7 mm long; lip with 3 ridges, without papillae  Eulophia tenella
2a Sepals more than 9 mm long; mid-lobe of lip with papillae  3
3 Lip with a central callus of 2 subquadrate, flap-like ridges  Eulophia alta
3a Lip lacking such a callus  4
4 Lateral sepals attached to column-foot, distinctly below insertion of ovary  Eulophia tanganyikensis
4a Lateral sepals not as above 5
5 Sepals green or bronze, petals white; lip green and purple with 3–5 rows of short papillae  Eulophia stachyodes
5a Flowers green; lip mid-lobe purple or purple and white, with many long papillae  6
6 Dorsal sepal 12–20 mm long; spur 2–2.5 mm long, conical  Eulophia elegans
6a Dorsal sepal 9–12 mm long; spur 1.5–3 mm long, cylindrical, incurved Eulophia kyimbilae 
7 Midlobe of lip lacking papillae 8
7a Midlobe of lip with papillae  9
8 Flowers showy, mauve-pink; petals erect, 18–23 mm long Eulophia livingstoneana
8a Flowers straw-coloured, or brownish with a violet lip; petals porrect, 6–8 mm long  Eulophia chilangensis
9 Spur 5–6 mm long, slender, straight, parallel to ovary  Eulophia obscura
9a Spur not as above  10
10 Flowers yellow and purple; spur 3–5 mm long, decurved; perennating organs pseudobulbous, covered with brown sheaths, mostly subterranean but usually with tip above ground  Eulophia monile
10a Flowers greenish or green-brown; spur 1.5–3 mm long, incurved, inflated at apex; perennating organs tuberous, subterranean  Eulophia monile syn. Eulophia norlindhii

World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; accessed 12/08/2019